Attachment for loom let-off mechanisms



Aug. 28, 1934. R. B. TRANSUE v ATTACHMENT FOR L OOM LET-OFF MECHANISMFiled May 9. 1932 INVENTOR.

ATTORNEY.

Patented Aug. 28, 1934 ATTACHMENT For: Loon r LET-OFF MECHANISMS "RogersB. Transue, C hambersburg, Pa. 7 Application my 9, [1932, Serial No.610,053 f '1 Claim. (01. 188.33)

My invention relates to attachments for loom let-off mechanisms.

Loom let-off mechanisms and used in the cloth weavingindustry are forthe purpose of exerting a constant and even ten sion on the warp beamsfrom which the threads are drawn and comprise an assembly of gearstogether with a weight so arranged that the necessary tension will beexerted on the threads as aforesaid. After some use, however, there is atendency of the gears to wear so that the warp beam may over run more orless independently of the let-01f mechanism causing a bad mark in thecloth being woven.

It is the main object of my invention to provide a device which may bereadily attached to a letoff mechanism after it has become worn withoutalteration thereof and which may then be as readily adjusted to providethe necessary frictional grip on one of the gear shafts so that saidgear and the let-off mechanism may be prevented from the over-runningdescribed above.

Another object is to provide an attachment for this purpose in a simple,inexpensive and eficient form.

The foregoing and other objects together with means whereby the same maybe carried into effect will best be understood from the followingdescription of a preferred embodiment of my invention taken inconnection with the accompanying drawing wherein:

Figure 1 is a side elevation-partly broken away, of a conventional formof let-oif mechanism showing my invention applied thereto.

Figure 2 is an enlarged side elevation partly broken away and insection, showing my inven tion alone.

Figures 3, 4 and 5 are plan views of the friction washer, adjustingwasher, and collar respectively which constitute the working parts of myinvention.

Referring now with more particularity to the drawing Figure 1illustrates a let-off mechanism of the type covered by Patent Number1,803,143

.lissued April 28, 1931 to Oscar V. Payne and my invention is shown asapplied to this mechanism though it is understood that it may be appliedwhen possible and desirable to all other types of mechanisms.

In the structure shown the reference character A designates a shaftwhich is extended from the warp beam B over which the warp threads Tpass forward to the usual lease rods and harnesses (not shown) of theloom (also not shown).

. worm gear C is attached to and rotates with as commonly knownthe shaftA and turns within a housing D which is normally pulled in acounterclockwise direction as viewed in Figure 1 by the weight E. A wormF meshing with the worm gear C and fixed on aishaft G journaled inthehousing D in effect acts to lock the housing on the worm gear and to thewarp beam B so that the clockwise movement or strain on the warp beam asthe threads T are drawn off acts to raise the weight E. A tension orstrain is thus exerted on the warp threads by the weight which is ofcourse selected to provide the proper warp tension. Additional mechanismis provided to cause a periodic rotation of the worm F in order that theworm gear C may rotate as the warp threads are drawn off while at thesame time the housing D will be held by the threads in such positionthat the weight E is pulled upward and exerts the desired tension on thethreads.

After some use the worm gear C and worm F become worn and the constantstrain imposed by the weight E on these gears will cause the worm gearto slip or turn backward in a counter-clockwise direction at timesresulting in a decrease or loss of the tension exerted by this weight onthe warp threads and causing a bad mark in the cloth being woven. It isto prevent this action that my invention is used.

My invention comprises a friction washer l of fibre or other suitablematerial and having an inner diameter such that it may slip freely overthe lower extended end of the shaft G. A pressure washer 2 of similarsize and dimensions but formed of metal is provided and has in one facethree, more or less, equally spaced sockets or depressions 3. A collar 4also of metal and having a bore 5 suitable to fit the shaft G isprovided and is of such thickness that threaded sockets 6 may beextended radially inward from its outer periphery into the bore 5 toreceive set screws '7 having head sockets 8 by means of which. they maybe adjusted by a tightening tool (not shown) Pressure screws 10 arethreaded through bores 11 in the collar 4 at equally spaced points andin parallelism with the axis of the bore 5 and have their ends 12rounded off to enter the depressions 3 in the pressure washer 2. Theopposite ends of the screws 10 have screw driver kerfs 13 and lock nuts14 are mounted on these ends to lock the screws in an adjusted position.It is understood that any number of set screws '7 or pressure screws 10may be employed and of course that the depressions 3 in the pressurewasher 2 will be provided in number and position to suit. In use thefrictionwasher 1 is slipped over the lower end of the shaft G and upagainst the lower edge of the housing D and the pressure washer 2 isplaced up against this washer 1 with its face bearing the depressions 3turned downwardly. The collar 4 is then placed over the shaft G andlocked in place by the set screws '7 and the pressure screws 10 engagedwith the depressions 3 and turned to exert a pressure on the pressureWasher. This of course presses the friction washer 1 tightly betweenwasher 2 and the lower edge of the housing D and restrains the shaft Gagainst over-running or other undesired movement under the pull exertedby the weight E as aforesaid by virtue of the frictional contact andengagement between the washers and housing. The necessary pressure toprevent loss of tension on the warp threads T having been secured bythis means the lock nuts 14 are of course tightened. Continuous andconvenient adjustment for wear is provided by the pressure screws 10 tocom pensate both for wear in the gears C and F and the friction washer1.

Obviously my attachment may be used in similar manner on othermechanisms wherever their construction permits and will in any caseprovide an efficient and convenient means for maintaining the mechanismin its proper operating condition.

While I have herein set forth a certain preferred embodiment of myinvention it is understood that I may vary from the same in details soas best to construct a practical device for the purposes intended, notdeparting from the spirit of the invention and within the scope of theappended claim.

I claim:

In a device of the kind described, the combination with a loom let-01fmechanism, a housing and a worm shaft extended from the housing of afibre friction washer mounted on the shaft next to the housing, a metalpressure washer mounted on the shaft next to the friction washer andhaving depressions in its face remote from the housing, a collar mountedon the worm shaft and spaced outwardly from the pressure washer, setscrews extended radially inward through the collar against the shaft tolock the collar to the shaft, and pressure screws threaded through thecollar parallel with the shaft and extended at their ends into the saiddepressions in the pressure washer.

ROGERS B. TRANSUE.

